Some communication terminals include a microphone, an ear speaker, and a loudspeaker. The ear speaker is configured to be placed adjacent to an ear for listening. The loudspeaker is configured to generate ring tones and/or for use as a hands-free broadcast speaker.
Background noise at the communication terminal can have numerous undesirable affects on communications through the communication terminal. For example, the background noise may obscure or mask the voice of a user that is sensed by the microphone and communicated from the communication terminal. Background noise can include wind noise and other noise sources, such as vehicles, voices from persons other than the user and/or background music. The background noise can also include feedback from the loudspeaker and/or the ear speaker through the microphone, which may also create an echo effect where, for example, a voice signal received from a user is fed back and heard by that user as an echo of their own voice. Some loudspeakers are located on an opposite side of the communication terminal from the microphone to reduce the amount of sound therefrom that is sensed by the microphone.
Some communication terminals include echo cancellation circuits that use multiple microphones to sense and reduce noise in a microphone signal, such as feedback from a loudspeaker through a microphone.